不同移栽期下气象因子与三门峡烤烟上部叶产量和品质的关系分析

为明确气象因子对三门峡烤烟上部叶产量和品质的影响,确立优质上部叶形成的关键气象指标,为合理调节烤烟移栽期提供理论依据,以烤烟主栽品种云烟87为材料,于2020—2021年在灵宝进行大田试验,研究不同移栽期烤烟上部叶发育期间气象因子、产量及品质,解析气象因子与产量和品质的关系。结果表明,三门峡上部叶各生育阶段气象因子随移栽期推迟均发生明显的改变,以成熟期气象因子变幅最大。随移栽期推迟,上部叶产量、产值、上等烟比例和均价呈先增后减的趋势;还原糖含量、糖碱比先升后降,烟碱含量逐渐降低;烟叶香气质、香气量及感官质量总分呈先升高后降低的趋势;5月7日移栽处理烤烟上部叶经济性状和品质最佳。相关分析表明,上部叶各经济指标、还原糖含量、烟碱含量、糖碱比、香气质、香气量及感官质量总分均与其成熟期日均温呈显著或极显著正相关。各气象因子与上部叶香气质、香气量及感官质量总分关联度大小顺序依次为温度、日照时数、降雨量,其中以成熟期日均温关联度最大;当成熟期日均温在20.20~25.16℃时,上部叶香气质、香气量及整体感官质量较佳。

烤烟上部叶带茎采烤技术SWOT分析

与常规采烤方式相比,采用烤烟上部叶带茎采烤技术,烟叶质量明显提升,经济性状表现优良,中上等烟比例上升,杂色烟叶明显减少。本文运用SWOT模型,分析了烤烟上部叶带茎采烤技术的优势、劣势、机会和威胁,并提出了优势—机会、弱点—机会、优势—威胁、弱点—威胁一系列发展策略,以期为烤烟上部叶带茎采烤技术的发展提供参考。

氮素在土壤中的转化及其对烤烟上部叶烟碱含量的影响

研究了烤烟生育期内植烟土壤中的氮素转化、供氮状况以及氮素对烤烟上部叶烟碱含量的影响。结果表明:施用无机氮肥可大幅度提高0～20cm深的土壤中的无机氮浓度,但维持时间较短;20～40cm深的土壤中无机氮的浓度受氮肥的影响较小;后期土壤供氮较多时易导致烤烟上部叶的烟碱含量过高。

成熟期灌水对烤烟上部叶质量的影响

为了研究成熟期灌水对烟株上部叶叶片开片情况、烤后物理特性和化学成分的影响,以K326为供试品种,在成熟期进行3种不同灌水管理,探讨成熟期灌水对烤烟上部叶质量的影响。结果表明:成熟期灌水后,烟株上部叶叶片面积增大,开片状况变好,烟叶物理特性较优,烟叶的还原糖和总糖含量升高,总氮和烟碱含量降低,尤其是在现蕾、打顶和圆顶时期灌水,烟叶化学成分协调性明显增强,中性致香成分含量丰富,有利于改善烟叶品质。

烤烟上部叶不同烘烤方式综合效果比较

以云烟105的上部叶为试验材料,设置带茎烘烤、不带茎烘烤2个处理,对比分析2个处理的综合效果。结果表明,带茎烘烤处理的干烟质量、每千克干烟叶能源消耗量、采烤环节人工成本与不带茎烘烤处理相接近,但带茎烘烤处理能够缩短烘烤总时间,显著减少挂灰烟,显著提高上等烟比例,提高烟叶均价,且烤后烟叶身份多呈现中等-稍厚,叶片结构疏松-稍密、偏向疏松,外观质量表现较好。

褪黑素、赤霉素与油菜素内酯对烤烟上部烟叶发育及产质量的影响

为明确褪黑素对烤烟上部烟叶发育的作用,为优质烟叶生产提供参考依据,采用单因素随机区组试验,以烤烟品种云烟105为试验材料,研究喷施褪黑素(MT)、赤霉素(GA3)和油菜素内酯(BR)对上部烟叶叶面积、单叶重、叶面积指数、产量产值及化学成分的影响。结果表明,GA3对上部烟叶的叶面积、叶面积指数和单叶重的促进作用最好,其次为BR,MT处理与对照(CK)没有显著差异。各处理上部烟叶的化学成分总体较为协调,均处在优质烟叶适宜的糖碱比范围内。其中,喷施GA3处理的总糖、还原糖、总氮和烟碱含量最高;喷施褪黑素处理对上部烟叶的钾含量增加显著,较对照增加了1.18个百分点。在所有处理中,以喷施褪黑素的烟叶产量与产值为最高,烟叶的总产量较对照增加了6.75%,每公顷总产值则较对照增加了4804.50元。3种激素喷施对上部烟叶的感官评吸质量均有提升作用,具体表现为GA3>BR>MT。其中,以喷施10 mg/kg GA3的效果最好;褪黑素喷施浓度为150μmol/L时,可以有效提升烟叶的产量和产值。

晾制时间对上部叶烘烤过程生理特性和烟叶品质的影响

为探究晾制时间对上部叶烘烤过程生理特性和烤后烟叶品质的影响,以K326的上部叶为试验材料,通过先晾后烤的方法,以当地常规烘烤(无晾制)模式为对照(CK),设置了T_(1)(晾制24 h)、T_(2)(晾制36 h)2种晾制时间,探究了先晾后烤处理对烟叶烘烤工艺、烘烤过程烟叶的生理特性及烤后烟化学成分和香气成分的影响,得出最适宜的晾制时间和烘烤工艺。结果表明:与常规烘烤相比,T_(1)、T_(2)处理在烘烤前含水率分别下降了2.81、3.03个百分点;T_(2)处理烘烤总用时下降了22 h,均价提高了4.13%;与CK相比,T_(2)处理烤后烟叶烟碱和总氮含量分别显著降低了1.16、0.35个百分点;T_(1)、T_(2)处理棕色化反应产物、苯丙氨酸裂解产物、类胡萝卜素降解产物总量均增加,T_(2)处理的香气总量提升了6.40%。综上所述,南平地区K326上部叶经过先晾后烤处理后烘烤用时缩短、经济性状好、烤后烟叶总体质量符合上部叶增效提质要求,其中T_(2)处理的效果整体表现最优。

移栽期对云烟97上部烟叶质量的影响

为缓解滇东北烟区上部烟叶成熟时低温造成的影响,提高上部叶的产质量,采用田间试验的方法,研究不同移栽时间对云烟97的上部烟叶农艺性状、生育期、表观特征、叶片组织结构、酶活性、经济性状、鲜干比、外观质量的差异,分析其对烟株生长发育以及产值量的影响。结果表明,4月21—25日移栽处理大田生育期最短,为113 d,该处理可提高上部烟叶SOD、PPO酶活性,降低NR酶活性和MDA含量,鲜干比、栅栏组织和海绵组织的比值均最小,成熟度最好,增加上部烟叶开片度及抗逆性,有利于烟株的生长发育,产量及产值最高,比4月26—30日处理初烤烟叶产量提高521.42 kg/hm~2,产值增加11 529.42元/hm~2,上等烟的比例达50.71%。因此,移栽期为4月21—25日时更有利于改善宣威烟区烤烟上部叶组织结构,提高上部烟叶的抗逆性、产量及外观质量。

密集烤房烘烤环境改变对烤烟上部位叶可用性的影响

为提高烤烟上部位叶可用性,通过向密集式烤房装烟室底层铺河沙进行保湿以改善烘烤环境。结果表明:铺河沙能有效降低单位干烟耗煤量及耗电量,降低烘烤成本;提高上等烟比例、均价及产值,改善烟叶经济性状;烟叶内在化学成分更加协调,感官质量提高,表现在烟叶的疏松度及烟叶深度增加,含青杂率降低,外观质量改善等。因此,在密集式烤房装烟室底层铺河沙,对提高上部位叶可用性具有重要意义,值得在烤烟生产上推广。

采收方式和成熟度对上部烟叶细胞结构及品质的影响

为研究烤烟上部叶采收的最适成熟特征,将云烟87上部叶按不同成熟度进行分次采收,通过外观质量和感官质量评价确定常规采收时间推迟5 d即移栽后125 d（M2阶段）对烤烟进行一次性采收,烟叶质量最优。其中移栽后125 d的顶3-顶1叶（TM2）的外观质量和感官质量评分为44.67和71.79;移栽后125 d的顶6-顶4叶（FM2）为43.36和71.75;均优于其他几个阶段。从叶片结构的细胞学变化规律看出,随着烟叶成熟度的提高,栅栏组织和海绵组织在移栽后125 d（M2阶段）开始变得疏松、细胞间隙增大、细胞中各种细胞器开始降解、淀粉颗粒积累到最饱满状态。其中移栽后125 d的顶2叶的栅栏组织厚度、海绵组织厚度、栅栏组织细胞密度和海绵组织细胞密度分别为145.3μm、144.7μm、43个/mm、43个/mm;移栽后125 d的顶5叶的栅栏组织厚度、海绵组织厚度、栅栏组织细胞密度和海绵组织细胞密度分别为139.7μm、148μm、42个/mm、41个/mm。该研究进一步证实M2阶段为烤烟上部叶采收最适成熟特征。

精益采收方式与成熟度对上部烟生理变化和感官的影响

针对当前烤烟上部叶生产中出现的问题,结合卷烟工业的需求导向,进行不同采收方式、不同成熟度的采收组合,研究其对大田生长后期烟叶主要生理指标和烤后烟叶的感官评吸的影响。结果显示,相比一次性采收上部叶1~6片,田间烟株分次采收顶部4~6片烟叶后剩余的顶1~3片叶中SOD含量明显降低,而MDA含量迅速提高,而且采收的顶1~3叶片内色素含量,和采收的顶4~6片达到显著差异程度。一次性采收上部叶时,顶1~3片叶与顶4~6片叶水分含量比率接近于1,不但能够缩小上部叶上、下叶位感官差异,还能够提高评吸得分。研究结果为烟草工、商业合作开发和利用上部叶提供了一条可行性思路。

Effects of Different Baking Processes on Carotenoid Content in Upper Leaves of Fluecured Tobacco

[Objective] We aimed to improve the quality of flue-cured tobacco with K326 upper leaves and explore the optimal tobacco baking process in Chongqing tobacco-producing region. [Method] Four different baking processes （endogenetic force moisture-removing flue-curing technique, exogenetic force moisture-removing flue-curing technique, three-stage flue-curing process, three-stage and six-step flue- curing process） were adopted in this research to investigate the effects of different baking processes on carotenoid content of same-maturity degree upper leaves of the flue-cured tobacco K326. [Result] The results showed at the yellowing and color fixing stages, the carotenoids were most fully decomposed in endogenetic force moisture-removing flue-curing technique. The decomposed carotenoid content was lowest in exogenetic force moisture-removing flue-curing technique, for which the carotenoid content was highest （50.53 mg/g）. [Conclusion] At the yellowing and color fixing stages, exogenetic force moisture-removing flue-curing technique was most conducive to the carotenoid accumulation in tobacco baking process.

Correlations between Quality Index and Content of Cellulose and Lignin in Upper Leaves of Fluecured Tobacco in Wulin Mountain Area

In order to study the correlations among quality indexes of tobacco leaf and contents of cellulose and lignin in upper leaves of flue-cured tobacco, 48 B2F flue-cured tobacco samples in seven counties of Wulin mountain area in 2011 and 2012 were used as test materials to measure the contents of cellulose and lignin in tobacco leaves and analyze the differences among varieties and between years. Meanwhile, correlations among contents of cellulose and lignin and appearance quality, physical characteristics, general chemical components and indexes of senso- ry quality were studied. The results showed that the contents of cellulose and lignin had no significant difference among years and varieties. Cellulose content was sig- nificantly correlated with some indexes of appearance qualities, physical indexes, general chemical compositions and sensory qualities. Lignin content was significantly correlated with grayness and oil content but not other quality indexes of tobacco leaf. It could be seen that the differences of cellulose and lignin contents between different years and among varieties were not significant. Cellulose content was closely correlated with quality indexes of tobacco leaf while lignin content had a small effect on tobacco leaf quality.

Effects of Different Flue-curing Barns on Aroma Quality of Upper Flue-cured Tobacco Leaves of K326

[Objective] This study was conducted to compare the aroma quality of up-per leaves of K326 flue-cured in different barns, and provide theoretical references for the development and optimization of bulk curing barn and the supporting tech-niques. [Method] The upper leaves of K326 were flue-cured in a commonness barn, a four-shelf bulk curing barn and a three-shelf bulk curing barn separately, and then the contents of aroma components and taste quality indices of the finished leaves were measured and compared. [Result] The contents of total aroma components, chromoplast pigment degradation products, phenylalanine aroma components and neophytadiene showed no significant differences in the leaves flue-cured in four-shelf bulk curing barn and commonness barn, but were significantly or very significantly higher than those in the leaves flue-cured in three-shelf bulk curing barn. The con-tents of carotenoid degradation products, Mail ard reaction products, cembranes aro-ma components and total aroma components （except neophytadiene） showed no significant difference among the three treatments. The results of sensory evaluation revealed that the sensory taste of the leaves flue-cured in four-shelf bulk curing barn was the best, as the finished leaves had rich, delicate aroma, comfortable and clean aftertaste. The leaves flue-cured in commonness barn was better than those flue-cured in three-shelf bulk curing barn in aroma quality, amount and aftertaste. [Conclusion] The four-shelf bulk curing barn had a large volume for tobacco leaf processing, but a similar baking environment to the commonness barn, which is conducive to the formation and accumulation of aroma components, so the finished leaves had similar appearance and quality with those flue-cured in commonness barn. The upper flue-cured leaves in three-shelf bulk curing bran had poorer quality than those flue-cured in the other two barns.

Judgment of Aroma Types of Middle and Upper Flue-cured Tobacco Leaves Based on Stepwise Discriminant Analysis

[Objective] The aim of this study was to establish mathematical models for judging the aroma types of middle and upper flue-cured tobacco leaves according to the contents and proportions of aroma compositions. [Method] The aroma types of tobacco leaves were judged based on stepwise discriminant analysis, using 63 C3F and 65 B2F tobacco leaf samples from 13 tobacco producing regions in 11 provinces of China （Huili in Sichuan, Baokang in Hubei, Wulong in Chongqing, Lu- oyang in Henan, Zhucheng in Shandong, Wuyi Mountain in Fujian, Malong in Yun- nan, Chuxiong in Yunnan, Bijie in Guizhou, Liuyang in Hunan, Suiyang in Guizhou, Kaiyuan in Liaoning, Nanxiong in Guangdong） as calibration samples, and 67 aroma components as indices. And the Fisher discriminant functions were verified using 21 C3F and 19 B2F tobacco leaf samples. [Result] Variation coefficients of the propor- tions were lower than that of contents of most aroma components in middle and upper leaves of the samples, indicating that the proportions were more stable than contents of aroma components. The proportions of benzyl alcohol, solanone, β-dam- ascone, neophytadiene, farnesylacetone A, palmitic acid, thunbergol, methyl linole- nate and cembratriene-diol were all over 1% in both middle and upper leaves, al- though the dominant aroma components of the same aroma type varied between middle and upper leaves. Moreover, 11, 18, 7 and 11 aroma components were re- spectively introduced into the Fisher discriminant functions established based on the contents and proportions of middle and upper flue-cured tobacco leaves, which ex- hibited accuracy rates of 91.7%, 100%, 91.7% and 91.7% in the judgments of other tobacco leaf samples. The results revealed that the components those determined aroma types in middle leaves were obviously more than in upper leaves. In middle leaves, the accuracy rates of aroma type judgment could be improved by using the proportions rather than the contents of aroma components as indices. However, the functions based on the proportions and the contents of aroma components in upper leaves gave close accuracy rates. [Conclusion] The results of the study will provide references for identifying aroma types of flue-cured tobacco leaves in future work.

Judgment of Aroma Types of Middle and Upper Flue-cured Tobacco Leaves Based on Proportions of Aroma Components

[Objective] This study aimed to establish mathematical models for judging the aroma types of flue-cured tobacco leaves from the upper and middle parts of plants. [Method] A total of 128 samples （63 C3F and 65 B2F） from 11 main tobac- co production provinces of China were selected as materials. Stepwise discriminant analysis was applied to samples with different aroma types and discriminant function was expressed with the proportions of 67 aroma components in total aroma con- stituents as the index. [Result] The ratio of most aroma components in clear and full aroma tobacco leaves was higher than that in middle aroma leaves. The ratios of 51, 43 and 40 aroma components of clear, middle and full aroma tobaccos were higher in upper leaves than that in middle leaves. Aroma components dominated certain aroma types differed between middle and upper leaves. The proportions of 18 and 11 aroma components in upper and middle leaves were led in the stepwise discriminant function respectively. Self-validation and cross-validation methods were applied to evaluate the original samples, and the accuracy rates reached 100% and 98.6% on middle leaves, 96.37% and 94.4% on upper leaves. The accuracy rates on some other samples reached 100% on middle leaves and 91.7% on upper leaves predicted with the model. [Conclusion] The ratio of aroma components as discriminant index could improve discriminant accuracy significantly in the middle and upper leaves. It could be used to analyze aroma types objectively, accurately and quickly.